Impurities in a crystal lattice are the key ingredient in recent efforts to control and apply the coherence and entanglement of spins in condensed-matter systems.

The idea that quantum mechanical machines can perform certain information-processing tasks much faster than any classical computer has captured the imagination of many people. That potential has led to a new era in quantum science, one in which researchers strive to identify and harness quantum systems and leverage them for computation, communication, sensing, and imaging. Two of the most promising platforms for reaching the coherence needed to achieve such goals are isolated atoms and solid-state devices...